Although this large (in European terms) and showy butterfly is called the Scarce Swallowtail in English, as anyone who observes Lepidoptera in France should be able to tell you, it isn't scarce at all (except maybe this year, which is poor for many butterflies). Its English name reflects its English status, that of an occasional migrant, turning up in Britain only about a dozen times in the last 300 years.
In France it is le Flambé ('the Singed') due to its pattern of charcoal stripes, as if it has had a flame passed over it. They appear in gardens in the spring, but it is the second generation, emerging in July, that is most noticeable in lowland central France. This one was photographed in Elsie's garden in Chinon last July. The caterpillar was photographed in le Petit Pressigny, in the garden of some friends. It was traversing the gravel to find somewhere to pupate in the leaf litter, where it would overwinter. The September caterpillars are browner in colour to provide better camouflage. Earlier in the year, when they pupate in the fruit tree host plant, they stay green.